We report the experimental results of temperature-dependent polarized As K-edge extended X-ray absorption fine structure (EXAFS) of LaFe1−xCoxAsO (x = 0.0 and 0.11) single crystals. By aligning the Fe–As bond direction in the direction of the X-ray beam polarization, we have been able to identify an anomaly in the Fe–As bond correlations at the tetragonal to orthorhombic transition at 150 K, while previous investigations with standard unpolarized EXAFS of undoped LaFeAsO powder samples were not able to detect any such anomaly. Using our approach, we have been able to identify in the superconducting doped sample, LaFe0.89Co0.11AsO, a broad anomaly around 60 K. The low-temperature anomaly has good correlations with the temperature dependence of several properties like resistivity, magnetic susceptibility and linear thermal expansion, indicating the emergence of the dynamical oscillations of the Fe–As pairs.
Temperature-dependent as K-edge EXAFS studies of LaFe 1−xCoxAsO (x = 0.0 and 0.11) single crystals / Boby, Joseph; Ricci, Alessandro; Poccia, Nicola; Ivanov, Valentin G.; Ivanov, Andrey A.; Menushenkov, Alexey P.; Saini, Naurang Lal; Bianconi, Antonio. - In: JOURNAL OF SUPERCONDUCTIVITY AND NOVEL MAGNETISM. - ISSN 1557-1939. - 29:12(2016), pp. 3041-3047. [10.1007/s10948-016-3785-7]
Temperature-dependent as K-edge EXAFS studies of LaFe 1−xCoxAsO (x = 0.0 and 0.11) single crystals
BOBY, JOSEPH;SAINI, Naurang Lal;
2016
Abstract
We report the experimental results of temperature-dependent polarized As K-edge extended X-ray absorption fine structure (EXAFS) of LaFe1−xCoxAsO (x = 0.0 and 0.11) single crystals. By aligning the Fe–As bond direction in the direction of the X-ray beam polarization, we have been able to identify an anomaly in the Fe–As bond correlations at the tetragonal to orthorhombic transition at 150 K, while previous investigations with standard unpolarized EXAFS of undoped LaFeAsO powder samples were not able to detect any such anomaly. Using our approach, we have been able to identify in the superconducting doped sample, LaFe0.89Co0.11AsO, a broad anomaly around 60 K. The low-temperature anomaly has good correlations with the temperature dependence of several properties like resistivity, magnetic susceptibility and linear thermal expansion, indicating the emergence of the dynamical oscillations of the Fe–As pairs.File | Dimensione | Formato | |
---|---|---|---|
Saini_Single-crystals.pdf
solo gestori archivio
Tipologia:
Versione editoriale (versione pubblicata con il layout dell'editore)
Licenza:
Tutti i diritti riservati (All rights reserved)
Dimensione
551.27 kB
Formato
Adobe PDF
|
551.27 kB | Adobe PDF | Contatta l'autore |
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.